I did. Gentus 6.1 (RedHat w/ a few mods) and Gentus 3.0.
They were ok, but not much more than RedHat.
I now use a Mandrake 7.1. Works fine out of the box, and
there are patches on the web. Search "abit linux" with Yahoo
or some such.
I use an unpatched 2.4.0-test2 kernel right now. No problems.
I don't use the ATA66, but there is support for the HPT366 driver
in the kernel. Don't know how well it works.
There is also an Abit BP6 mailing list. Worth joining, perhaps.